speaking as a second generation fixed income lad, with an interest in real estate, I ended up doing well with real estate lending in order to move the yields up over 10%....second mortgages for self employed, first mortgages on commercial condos, gas stations, that sort of thing.
there is a science to this which you can read about. It can take some effort to get accepted by the good brokers. If you don't learn the rules and follow the rules, you WILL get creamed, and quite thoroughly.
If I had followed the rules I knew, I would have been FIRE at 50 instead of 55. Rule I broke was "don't place loans to personal friends of the broker"....the general rule is make sure the lawyers, the brokers and the borrowers are all arms length from each other, not dependent on each other for business, so that you are controlling the situation, and not being controlled.
This would however be a scary thing to be in in certain parts of the world, but with low Loan to Values, not necessarily so, especially with first mortgages.
One almost sure way to making money is to carefully buy houses in college towns and rent rooms to students. Once again, there is a science to this and it is labour intensive.
Another angle I saw real estate guys use (that were my borrowers) was to find active government subsidy programs and milk them, like for improvements to buildings in target neighbourhoods or for low income housing or for energy efficiency.
Another angle was to buy multifamily rental townhouse developments and split them into condos.